Method and electronic device for removing echo flowing in due to external device

Abstract

An electronic device according to various embodiments comprises a communication module including communication circuitry, at least one microphone, and a processor. The processor can be configured to: be connected to an external device through the communication module; switch a call audio signal path to an external device output path in response to being call-connected to an opponent device; duplicate a call audio signal (Rx in) transmitted from the opponent device, provide a first signal to an echo removal module, and provide a second signal to the external device via the external device output path; measure latency between the external device and the electronic device; variably adjust the size of a dynamic buffer for removing echo, by applying the measured latency; generate a reference signal delayed in the second signal, by the adjusted dynamic buffer; and remove an echo signal, with respect to the first signal generated from a speaker of the external device, from a microphone input signal obtained from the at least one microphone, based on the generated reference signal.

What is claimed is: 
     
         1 . An electronic device comprising:
 a communication module comprising communication circuitry;   at least one microphone;   a processor including processing circuitry; and   memory storing instructions   wherein the instructions, when executed by the processor, cause the electronic device to:   make a connection with an external output device through the communication module;   switch a call audio signal path to an external device output path in response to a call connection with a counterpart device;   provide, to an echo cancellation module of the processor, a first signal which is a copy of a call audio signal received from the counterpart device;   provide to the external output device through the external device output path, a second signal which is another copy of the call audio signal;   obtain, through the at least one microphone, an echo signal corresponding to the second signal and which is output from a speaker of the external output device;   measure a latency between the echo signal and the first signal provided by the echo cancellation module;   adjust a size of a dynamic buffer for echo cancellation processing based on the measured latency;   generate a reference signal by delaying the first signal by the adjusted size of the dynamic buffer; and   remove the echo signal from a microphone input signal obtained from the at least one microphone based on the generated reference signal.   
     
     
         2 . The electronic device of  claim 1 , wherein the instructions, when executed by the processor, cause the electronic device to switch the call audio signal path to the external device output path in response to a condition of activating a speakerphone function and accepting the use of an external output device according to the connection with the counterpart device. 
     
     
         3 . The electronic device of  claim 1 , wherein the instructions, when executed by the processor, cause the electronic device to execute a screen sharing module, based on acceptance of the use of the external output device and provide the second signal to the screen sharing module, and
 wherein the screen sharing module is configured to support a screen mirroring function of providing at least one of image data and audio data to the external device connected to the electronic device.   
     
     
         4 . The electronic device of  claim 1 , wherein the instructions, when executed by the processor, cause the electronic device to measure latency through at least one of an audio profiling scheme of calculating latency by analyzing log information indicating a point of each layer at which specific audio data is checked based on the specific audio data moving, an inaudible frequency scheme of calculating latency through an inaudible frequency output, and an ultra-wideband (UWB) scheme of calculating latency through a UWB signal. 
     
     
         5 . The electronic device of  claim 1 , wherein the instructions, when executed by the processor, cause the electronic device to:
 increase the size of the dynamic buffer based on the measured latency being larger than latency applied to the dynamic buffer; and   decrease the size of the dynamic buffer based on the measured latency being smaller than latency applied to the dynamic buffer.   
     
     
         6 . The electronic device of  claim 5 , wherein the instructions, when executed by the processor, cause the electronic device to record zero data in the increased dynamic buffer to generate the reference signal based on there being no data to be recorded in the reference signal before the latency is measured. 
     
     
         7 . The electronic device of  claim 5 , wherein the instructions, when executed by the processor, cause the electronic device to generate the reference signal by dropping a part of the first signal by the decreased size of the dynamic buffer in response to the decrease in the size of the dynamic buffer. 
     
     
         8 . The electronic device of  claim 1 , further comprising a camera,
 wherein the microphone comprises a plurality of microphone arrays, and   wherein the instructions, when executed by the processor, cause the electronic device to:   receive speaker identification information through the camera; and   beamform and amplify a microphone input in a direction in which a speaker is located among respective microphone inputs and cancel an echo signal for the first signal generated by the speaker of the external device from the amplified microphone input signal.   
     
     
         9 . A method of cancelling echo flowing into an electronic device by an external device, the method comprising:
 making a connection with an external output device through a screen sharing function;   switching a call audio signal path to an external device output path in response to a call connection with a counterpart device;   providing, to an echo cancellation module of a processor, a first signal which is a copy of a call audio signal received from the counterpart device;   providing to the external output device through the external device output path, a second signal which is another copy of the call audio signal;   obtaining, through at least one microphone of the electronic device, an echo signal corresponding to the second signal and which is output from a speaker of the external output device;   measuring latency between the external device and the electronic device;   adjusting a size of a dynamic buffer for each cancellation processing based on the measured latency;   generating a reference signal delayed from the first signal using the adjusted dynamic buffer; and   cancelling an echo signal for the second signal generated by a speaker of the external device from a microphone input signal acquired from at least one microphone, based on the generated reference signal.   
     
     
         10 . The method of  claim 9 , wherein the switching to the external device output path comprises switching the call audio signal path to the external device output path in response to a condition of activating a speakerphone function and accepting the use of an external output device according to the connection with the counterpart device, and
 wherein the providing of the second signal to the external device comprises executing a screen sharing module, based on acceptance of the external output device and providing the second signal to the external device through the screen sharing module.   
     
     
         11 . The method of  claim 10 , wherein the adjusting the size of the dynamic buffer comprises increasing the size of the dynamic buffer based on the measured latency being larger than latency applied to the dynamic buffer and decreasing the size of the dynamic buffer based on the measured latency being smaller than latency applied to the dynamic buffer. 
     
     
         12 . The method of  claim 11 , wherein the generating of the reference signal comprises recording zero data in the increased dynamic buffer to generate the reference signal based on there being no data to be recorded in the reference signal before the latency is measured. 
     
     
         13 . The method of  claim 9 , wherein the measuring of the latency comprises performing measurement through at least one of an audio profiling scheme of calculating latency by analyzing log information indicating a point of each layer at which specific audio data is checked based on the specific audio data moving, an inaudible frequency scheme of calculating latency through an inaudible frequency output, and an ultra-wideband (UWB) scheme of calculating latency through a UWB signal.